Let us first try to understand what exactly is a green roof. It is a roof of a building that is covered with vegetation, either partially or completely, over a water proofing membrane. It is a proper method of growing plants on the roof top and does not refer to green colored roof tiles. Green roofs are also known as "eco-roofs" and are divided into two main types, namely, intensive and extensive.
There is semi-intensive roofing as well which requires less deep soil than intensive roofing. Along with the depth of soil, intensive roofing, often referred to as traditional roof gardens, require feeding, irrigation, more labor and overall maintenance. Extensive roofing, on the other hand, is self-sustaining, grown on a very thin layer of soil and requires less maintenance, probably just a yearly weeding or so.
Benefits of Green Roof
Through these green roofing systems, both humans and the environment benefit equally and so these green roofs are gaining popularity day by day.
Natural Habitat for Birds and Insects
Man has captured major areas of land and transformed them into huge buildings which has severely affected the environment and the natural habitat of birds and insects. This applies especially to urban areas where the landscape is sealed by human building activities. But green roofing compensates for that. It creates a natural habitat for creatures like bees, grasshoppers and other insects, who find their food on these roofs and feel closer to their natural habitat.
Modern roofs need a lot of energy to moderate the temperatures in winter and summer. Whereas green roofs offer greater insulation and reduce the amount of energy required for moderating temperatures, thus making them energy-efficient.
Maintains Fresh Air
We all know that plants absorb carbon dioxide and release oxygen. The grass or the plants on the green roof not only absorb a huge amount of carbon dioxide but also absorb a number of pollutants present in the air. This green vegetation becomes a kind of natural air conditioner preventing air pollution.
Retains Storm Water
As vegetation requires a water supply, there is an inbuilt water retention layer in the green roof system. This layer is beneficial to retain otherwise wasted storm water. When it rains, because of this water retention capacity, you don't have to water the green roof vegetation. It uses the rainwater and prevents wastage. During heavy rains, rainwater runs off the flat or slanting roof and causes tremendous overflow in the sewage. A green roof prevents this overflow by slowing down the velocity and volume of running water. Researchers have also found that the nitrogen and phosphorous in rainwater is reduced by a green roof system.
Protects the Roof
During the construction of the structure/house, every builder installs a water proofing membrane to protect the structure/house from difficult weather conditions. Many people think that green roofing might adversely affect the water proofing membrane of the roof. But rather, it protects the membrane from ultraviolet radiation and micro-tearing caused by the constant exposure to weather fluctuations.
Increases Aesthetic Value
Green roofs can compensate for the lost greenery in urban areas and increase the aesthetic value of an area. Your building will look beautiful, coated with green vegetation. These roofing systems can serve as local community gardens. In addition to the attractive look, it will also create a natural atmosphere around you, causing physical and psychological benefits like reducing stress levels in people and keeping them physically fit.
Offers Recreational Space
Nowadays, there is no space left for recreational activities like social gatherings, kids' activities and other community functions. Green roof systems are capable of offering space for all these activities. People can start their own small-scale cultivation and experience the pleasure of gardening.
Increases Property Value
As green roofing is highly energy-efficient, it can act as an incentive for people who are interested in green roofing systems and their benefits. It will increase the market value of the building and fetch the owner, a great share of profit. It becomes an important asset to the property for which consumers are ready to spend hundreds of dollars. According to studies carried out in the U.S., a green roofing system can add almost 15% to the property value.
Every useful thing has some negatives or drawbacks. Green roofing too, has a few disadvantages. I just want to make you aware of some difficulties associated with such a roofing system. Firstly, it weighs a lot and old buildings might not be able to bear it. So be careful before you install it on a very old building. Secondly, the method of building a green roof system is a little difficult, and if you make even a small mistake, everything might just go down the drain. Lastly, the initial cost of green roofing is considerably high. Hence, if you have proper way out for the above difficulties, go ahead and install a green roof system.